Basicially to push it further, I would suggest figuring out where the light sources are coming from. You have a light source behind him, which should produce a halo effect on the hair and all edges where it has a chance to reflect off of. That light source seems to be nearly ignored in your picture.

The next bit of lihgt is the fill lihgt in front bringing out his features. Depending on where you look, both of his hands, his chest, his face, each surface in the front is recieving light in totally different places and from totally different locations. It looks like you mainly want to use a light coming from underneath, as seen by his face and a couple of differnt areas, such as one of the nads and neck. The direction this lihgt is coming from gets muddled espescially if you look at either hand. In one the light source looks like it's coming from the right, in the other it's coming from the right, but also from above.

The light on his chest looks like you're trying to kind of make some illumination come from the heart, but it's not totally coming through. Try different coloured light for different lihgt sources. You don't need to have light coming from the heart directly, it can bounce off the chest and help to illuminate other parts of the body.

The light on the neck and face can be done. If you look at something like Kingdom Come by Alex Ross, you can see that the light from below hleps to give the characters a slightly unreal or godlike look. Usually you wouldn't do that, but if you can get it to work good on you.

Lastly I would push your values a little more. The whites are nice and white, but areas which are in shadow, or are darker aren't dark enough to give the full effect of existing in space.

Lastly I just have to say the mouth looks creepy.

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